Mechanism for unwinding mill rolls



G. W. SWIFT. JR

MECHANISM FOR UNWINDING MILL ROLLS Aug. 11, 1936.

Filed March 20, 1934 \N mm ww ENTOR uh AM: RM

Patented Aug. 11, 1936 UNITED STATES PATENT OFFICE MECHANISM FOR UNWI NDING MILL ROLLS Application March 20, 1934, Serial No. 716,499

9 Claims.

This invention relates tomechanism for unwinding mill rolls and has for its object to pro-- vide animproved construction and arrangement of parts in a device of this character whereby power may be applied to a continuous web for drawing it from a heavy mill roll without unduly affecting the tension under which the continuous web is supplied to other mechanisms which are to operate thereon.

One of the objects of my invention is to provide mechanism of improved construction for unwinding mill rolls which while operating on the mill roll through the web, operates to maintain a substantially constant tension in the web supplied thereby to another mechanism.

Another object of my invention is to provide an improved simplified construction for a'device of this character which can be economically constructed; which operates directly and effectively upon the continuous web for regulating the tension under which the continuous web is supplied to another mechanism within certain desired limits; and which is immediately responsive tovariations in tension in the web.

In the embodiment shown on'the drawing, my invention contemplates more especially a device of this character suitable for feeding one of the webs of a corrugated paperboard machine such as that shown, described and claimed in my. copending application Serial No. 721,528 which was filed on the 20th day of April, 1934.

Certain specific novel features of construction will be described in the specification and recited in the appended claims, reference being hadto the accompanying drawing which exemplifies my invention in its adaptation to the corrugated paper board machine shown in my above-identified copending application.

Figure l is a side elevation of a preferred embodiment of my invention.

. Figure 2 is a top plan view of thesar'ne, parts being broken away and parts'shown in section.

Figure 3 is a central vertical longitudinal section of Figure 2.

Figure 4 is a schematic diagram of the. powertransmitting connections for upper and lower frictional feed belts and the overspeed web-feeding rolls. r

A -preferred embodiment of my invention is shown on r the drawing which illustrates an adaptation of the invention to the unwinding of a continuous liner web from a mill roll for supplying it to a single-faced corrugated web in the manner shown and described in my above-identified cop'ending application.

Referring more particularly to the drawing, a power shaft I which may be the side drive shaft of the corrugated paper board machine shown in my above-identified application, carries a sprocket wheel'Z which is connected by a sprocket chain? to a sprocket wheel 4 on a counter shaft 5, said counter shaft being journaled in suitable bearings 6 and I mounted on a laterally projecting portion 8 of a stationary support or side beam 9 which is spaced laterally from a second stationary support or side beam I0. In the preferred embodiment of my invention, parts 8, 9 and I constitute portions of the main longitudinal base frame of the corrugated paper board machine. Keyed to the forward end of the counter shaft is a bevel pinion II which meshes with a second bevel pinion I2 journaled in a bearing bracket I3 which is mounted on the portion 8 of the main baseframe. The laterally spaced stationary supports or side beams 9 and I0 serve to slidably mount a carriage which has a frame comprising laterally spaced bearing blocks I4 and I5 which are rigidly connected by ai-plurality of transverse stay shafts I6, I1 and I8, said stay shafts being rigidly secured at their opposite ends to the bearing blocks I4 and I5 by means of cap screws I9. As shown best in Figure 2 of the drawing, the bearing blocks I4 and I5 are provided with bearing bosses 20 for journaling a series of continuously driven transverse live shafts 2 I, 22 and 23 which carry spaced powerd'r-iven web-feeding rolls 24, 25and 26. Asshown bestin-Figure 3 of the drawing, said web-feeding rollsare journaled upon spaced parallel axes arranged in a common plane. Suitable means for connecting theweb-feeding rolls to rotate in unison with each other, may be provided by'spur gears 21, 28- and 29 which are respectively keyed to the live shafts 2 I ','22 and 23. As shown in Fig ure;2 of the drawing, the bevel'pinion I2 is splined to -thezoiiter' end of shaft'ZI by means of a spline 30. Mounted on the'stayshafts I6 and I I are flanged disks 3| and 32 which serve to carry lat erally'spaced side edge guides oriplates. 33 for cating, the continuous web axially with'respect to the web-feeding rolls. Referring now to Figure 3 of the drawing; a continuous web or a liner sheet which is drawn from a mill roll in a manner to be hereinafter referred to, passes over the stay 'shaft Ifi above and part-way around the web-feeding r011 26,-.thence downwardly under and part-way around. the web-feeding roll 25, thence upwardly over and part-way around the webf'eeding roll 24,'after which said web slides over the stay shaft I1 and under a guide roller 35 which is freely journaled upon the stay shaft l8. According to the present embodiment of my invention, the continuous web next passes upwardly over one of the arcuate heating units 36 of a curved heating table over which the liner web is drawn preliminarily to being applied to the single-faced corrugated web. Referring again to Figure 2 of the drawing, guide blocks 31 are mounted on the laterally spaced stationary supports or side beams of the main frame for slidably engaging the opposite ends of the bearing blocks l4 and [5 for guiding the transverse sliding movements of the carriage. Mounted on the stationary support or side beam 9 centrally of the carriage, is a bracket arm 38 for journaling an adjusting screw 39 which is threaded into the bearing block l5 and provided with a crank arm 40 by means of which the lateral adjustments may be imparted to the carriage.

A schematic diagram of some of the powertransmitting connections shown and described in my above-identified copending application is illustrated in Figure 4 of the drawing, according to which the continuous web 34 is unwound from a mill roll 34 by the web-feeding rolls 24, 25 and 26 which operate intermittently on the web 34 whenever momentary slight increases in tension in said web draw it into frictional engagement With the rolls so that as the web moves upwardly over the preheating arcuate plates 36, 36, under the action of frictional feed belts 69 and 18 to be presently more fully referred to, it is maintained under a substantially constant tension and velocity during its progressive attachment to the single-faced corrugated web which takes place immediately after the silicate adhesive has been applied to the downwardly presented crowns of the corrugated web. As the liner web 34 is applied to the singe-faced web after a preliminary heat treatment as it passes upwardly over the arcuate heating table comprising plates 36, the completely assembled webs move forwardly over the flat heating plates Bl and cooling plate 68 under the action of the upper and lower frictional feed belts. As shown in Figure 4 of the drawing, the upper frictional feed belt 10 travels over a rear follower drum l4 and. a front driving drum 83, to the latter of which it is pressed by a guide drum 81. The drum 83 which drives the upper endless feed belt 10, is mounted on a cross shaft 84 and rotated at the same peripheral speed as a drum 9| on a cross shaft 92, said cross shafts 84 and 92 being connected together to rotate in unison by means of intermeshing gears (not shown on the drawing). The lower frictional feed belt 69 is driven by the drum 9| to which it is pressed by a guide drum 94. The frictional feed belts 69 and 10 are driven at a common variable overspeed Velocity with respect to the double-faced corrugated board through a variable speed transmission comprising adjustable cone pulleys I00, belt lfll, and adjustable cone pulleys I02, the last-mentioned cone pulleys being connected by bevel gears I04, I04, to the common power shaft l. The driving connections for rotating the web-feeding rolls 24, 25 and 26 are such that the peripheral speed of said rolls is slightly in excess of the substantially constant normal velocity of the liner web 34 as it is applied to the single-faced corrugated web. At the same time, it will be understood that the continuous web 34 in passing from the web-feeding roll 24 to the web-feeding belts 69 and 10, is constrained to move over a path of unchanging length by means of stay shaft I 1, guide roller 35, and arcuate plates 36, 36. In consequence, at each recurring slight increase in tension in the liner web 34, said web is drawn into sufficient frictional engagement with the web-feeding rolls 24, 25 and 26 to enable said rolls to draw on the mill roll for an additional supply of the continuous web. This operation takes place automatically and substantially continuously in such a way that the liner web 34 is maintained under practically constant tension while it is being progressively united to the single-faced corrugated web. It will be understood from the foregoing description that for any preestablished conditions of heat, moisture, and velocity, under which the single-faced corrugated web is supplied, the bottom liner web may be maintained under a substantially constant tension by the automatic operation of the web-feeding rolls 24, 25 and 26, while at the same time the relative tensioning of the several webs composing the double-faced corrugated paper board may be readily effected at will while the machine is running by regulating the variable overspeed velocity of the frictional feed belts which operate on the corrugated board. It will be understood that by watching the condition of the paper boards coming from the machine, any inequalization in the relative tensioning of the several webs resulting in the displacement of one web relatively to another and a tendency to injure or break down the adhesive bond between adjoining webs during an extended drying and curing stage, may be noted at once and immediate steps taken while the machine is running. At the same time, it becomes possible by slight speed adjustments to eliminate all tendencies in the doublefaced corrugated paper board to warp or curl.

I claim:

1. In mechanism of the character described, the combination with a series of spaced powerdriven web-feeding rolls the web passing over and under said rolls in succession, means for driving said web-feeding rolls with equal peripheral velocities in excess of the normal speed of said web, side edge guides for retaining said continuous web in predetermined axial position with respect to said rolls, and means for adjusting said rolls and side edge guides together axially of said rolls.

2. Mechanism of the character claimed in claim 1, in which said web-feeding rolls are journaled about axes arranged in a common plane and geared together to rotate in unison in alternately opposite directions.

3. In mechanism for unwinding mill rolls, the combination with a carriage which is laterally adjustable with respect to the path of a continuous web coming from a mill roll, of a plurality .of spaced web-feeding rolls rotatable about parallel transverse axes on said carriage, said web feeding rolls being geared together to rotate in unison in alternately opposite directions, said web-feeding rolls being constructed and arranged to frictionally engage a web moving alternately over and under said rolls, means for driving said web-feeding rolls to impart a peripheral velocity to said rolls in excess of the linear speed of said web, and lateral edge guides for said continuous web mounted on said carriage.

4. In mechanism for unwinding mill rolls, the combination with stationary laterally spaced supports, of a carriage frame slidable transversely on said stationary laterally spaced supports, said carriage being provided with laterally spaced bearing blocks, a plurality of spaced webfeeding rolls journaled in said bearing blocks about parallel axes arranged in a common plane and geared together to rotate in unison, said web-feeding rolls being constructed and arranged to frictionally engage said web in alternation above and below said common plane, a powerdriven shaft rotatably mounted on one of said stationary supports, operating connections between said power-driven shaft and one of said web-feeding rolls for imparting thereto a periph eral velocity to said rolls in excess of the linear speed of said web, and means for laterally adjusting said carriage on said stationary supports.

5. In mechanism for unwinding mill rolls, the combination with a stationary base frame extending longitudinally of the path of a continuous web drawn from a mill roll, of a carriage slidable transversely on said stationary base frame, a plurality of web-feeding rolls rotatable about parallel axes arranged in a common plane, said web-feeding rolls being journaled in said carriage and geared together to rotate in unison in alternately opposite directions, a power-driven shaft journaled in said stationary base frame rotatable about a fixed axis extending longitudinally of the path of said continuous web, operating connections between said power-driven shaft and one of said web-feeding rolls, said web-feeding rolls being constructed and arranged to frictionally engage said web one after another and alternately over and under said rolls, and means for laterally adjusting said carriage on said stationary base.

6. In mechanism of the character described, the combination of means for feeding a continuous web under a substantially constant tension and velocity, a power-driven web-feeding roll having a peripheral velocity in excess of the substantially constant velocity of said web, means for constraining said web to a path of unchanging length extending between said web-feeding roll and said web-feeding means, said web-feeding roll being arranged to have web-feeding engagement with said continuous web for drawing additional web from a source of supply when under a tension in excess of the substantially constant tension under which the web moves over said path of unchanging length.

'7. In mechanism of the character described, the combination with means for feeding a continuous web under a substantially constant tension and velocity, of a power-driven web-feeding roll for drawing additional web from a source of supply and feeding it to said web-feeding means for reducing the tension in the web, means for driving said web-feeding roll at a peripheral velocity in excess of the substantially constant linear velocity of. said continuous web, and means for constraining said continuous web to a fixed path of constant length during its movement under substantially constant tension from said power-driven web-feeding roll to said webfeeding means, said web-feeding roll being arranged to have the continuous web drawn into feeding engagement therewith at recurring intervals due to the forward movement imparted to the web by said web-feeding means.

8. In mechanism of the character described, the combination with means for feeding a continuous web from a source of supply at substantially constant velocity, of a web-feeding roll arranged in the path of said continuous web between said source of supply and web-feeding means, said web-feeding roll having a peripheral velocity in excess of the velocity of said web, and means for constraining said continuous web to a path of unchanging length between said webfeeding roll and web-feeding means, said continuous web being drawn into intermittent feedsaid web.

9. In a machine of the character described, the V combination with peripherally -spaced webfeeding rolls rotatable about fixed parallel axes and arranged to frictionally engage alternately opposite surfaces of said web for unwinding the web from a mill roll at recurring intervals of time, web-feeding means for feeding said web at substantially constant velocity past and away from said web-feeding rolls, power connections for driving said web-feeding rolls at a peripheral velocity in excess of said substantially constant velocity of said web, and means for constraining'said continuous web to a fixed path between said web-feeding rolls and web-feeding means, said continuous web being tightened into feeding engagement with said web-feeding rolls at recurring intervals for maintaining said web under substantially constant tension.

GEORGE W. SWIFT, JR. 

